We shall study the nature of the platinum pyrimidine blues, using the following physico-chemical techniques: visible, ultra violet, infrared and Laser Raman spectroscopy; chemical analysis; proton NMR; EPR; ultracentrifugation; electrophoresis; and column chromatography. We will investigate the kinetic and thermodynamic parameters of the reactions of these complexes with proteins and nucleic acids. We will synthesize additional complexes of this class and test these for antitumor activity. We will study the significance of the lymphocytic infiltration of the kidneys of mice treated with cis-dichlorodiammineplatinum (II). We will study further the use of these platinum-pyrimidine complexes as electron-dense stains for electron-microscopy to determine the nature of the special surface binding sites on tumorigenic cells. We will study the kinetics of tumor cell growth in therapeutically treated mice.